Hyaluronic acid--syneretic glycosaminoglycan.

Hyaluronic acid from different sources, umbilical cord, vitreous, rooster comb and streptococcus, all exhibit a unique hydration behavior. Each hyaluronic acid and each different salt form has a maximum non-freezable water content at a set concentration beyond which the bound (non-freezable) water decreases. This type of behavior indicates a syneretic process simply due to concentration alone.

Hydration properties of lens crystallins.

The water binding properties of bovine lens crystallins, alpha, beta H, beta L and low molecular weight (LMW), were investigated with different techniques. The water sorptive capacity was obtained in high vacuum sorption experiments volumetrically, and also gravimetrically in controlled atmosphere experiments. The two methods gave reproducible isotherms.

Bound water content of bovine lens capsules.

The anterior parts of bovine lens capsules have been incubated in media with different glucose contents. The freezable water content of the lens capsule was obtained by differential scanning calorimetry and the total water content by thermogravimetric analysis. The bound (nonfreezable) water content was calculated as the difference between total and freezable water.